CHIRAL SEPARATION OF ALPHA-AMINO-ACIDS BY LIGAND-EXCHANGE CAPILLARY-ELECTROPHORESIS USING N-(2-HYDROXY-OCTYL)-L-4-HYDROXYPROLINE AS A SELECTOR

The direct chiral resolution of underivatized alpha-amino acids by cap illary zone electrophoresis (CZE) based on the principle of ligand exc hange is described. An N-(2-hydroxyoctyl)-L-4-hydroxyproline/Cu(II) co mplex was used as a chiral selector. Besides amino acids containing ar omatic residues, the basic amino acid histidine was resolved. Baseline separations were obtained for all amino acids investigated. The influ ence of selector concentration, electrolyte composition and pH on the resolution was investigated. It was found that there is a correlation between pI of the amino acids and the optimal pH.